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A198189 Primes from the decimal expansion of the golden ratio, phi, sorted first by the final digit index and then by length. 0
61, 3, 3, 1618033, 7, 887, 9887, 39887, 339887, 1618033988749, 89, 8874989, 398874989, 803398874989, 61803398874989, 2, 5, 3, 83, 683, 458683, 3, 43, 5, 3, 563, 6563, 36563, 868343656381, 180339887498948482045868343656381, 11, 811, 58683436563811 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

For the first two digits, none of 1, 6, and 16 are prime.

The next digit, 1 is not prime, but 61 is, so a(1) = 61. 161 is not prime, so it is not included.

PROG

(PARI) v=[1, 6, 1, 8, 0, 3, 3, 9, 8, 8, 7, 4, 9, 8, 9, 4, 8, 4, 8, 2, 0, 4, 5, 8, 6, 8, 3, 4, 3, 6, 5, 6, 3, 8, 1, 1]

for(n=1, #v, x=0; p=1; forstep(k=n, 1, -1, x+=p*v[k]; p*=10; if(v[k]&&isprime(x), print1(x", "))))

CROSSREFS

Cf. A186205.

Sequence in context: A241601 A132096 A051322 * A102600 A316918 A077331

Adjacent sequences:  A198186 A198187 A198188 * A198190 A198191 A198192

KEYWORD

nonn,base

AUTHOR

Franklin T. Adams-Watters, Oct 21 2011

STATUS

approved

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Last modified July 10 23:30 EDT 2020. Contains 335600 sequences. (Running on oeis4.)